Color-changing dental compositions can be advantageous for use in a wide variety of dental and orthodontic applications. For example, a hardenable dental composition having an initial color that provides a visible contrast to the color of the tooth structure can aid the practitioner in properly placing or identifying the hardenable composition, after which the color preferably changes to colorless or tooth color to minimize visibility of the composition. Examples of such color-changing dental compositions include dental sealants, in which the initial color can aid the practitioner in accurately placing the composition in and/or on desired pits and fissures. Additional examples of such color-changing dental compositions include adhesives (e.g., dental and orthodontic adhesives), in which the initial color can aid the practitioner in removing excess or unwanted adhesive from the tooth structure.
Certain color-changing, hardenable dental compositions (preferably light-curable dental compositions) that include a photobleachable dye have found use in a variety of dental and orthodontic applications. For example, the photobleachable dye can impart an initial color to the composition to aid in placement of the composition in and/or on the desired areas of the tooth structure. After the practitioner determines that the hardenable dental composition has been properly placed or removed, exposure to actinic radiation (e.g., to harden a light-curable composition) can cause loss of color of the photobleachable dye (i.e., bleaching), thus minimizing visibility of the hardened dental composition.
Self-etching dental compositions are finding increasing utility in the dental and orthodontic areas. However, there exists a need for self-etching dental compositions that have useful color-changing properties.